Air heating box for textile machines

ABSTRACT

An insulated air heating box for treating threads transported by textile machinery wherein one wall of the box is provided with entry and exit slots for each thread together with an adjustable thread loading and guiding means insertable through the same wall between or adjacent to the thread entry and exit slots. The box is also equipped with one or more different heating devices, permitting contact-free heating of the threads and/or direct heating on a contact plate arranged within the box. This invention generally relates to an air heating box for the heat treatment of a plurality of yarns or threads which usually move in approximately vertical direction as they are transported by conventional textile machines, especially in texturizing, stretching, stretch-spooling, stretch-twisting or stretchtexturizing machines. Thus, it is often essential in working with synthetic, thermoplastic polymer filaments, threads or yarns to achieve a continuous heat treatment thereof, e.g. for stretching, twisting or texturizing purposes, the same treatment being simultaneously applied to a large number of threads as they are rapidly transported in the textile machine. For the achievement of uniform quality in each individual thread and also equal quality of all of the threads among one another, it is generally desirable that the threads be exposed to the same temperature at all points during their passage in or through the air heating box. One known air heating box has in its interior a large number of U-shaped, electrically heated tubes or rods arranged perpendicularly and transversely to the longitudinal direction of the heating box, additional heating tubes or rods being provided in the region of the heating box base. Between each pair of the threads running from top to bottom once through the rectangular or block-shaped heating box and the heating tubes or rods allocated to these threads, there is arranged a substantially Ushaped sheet metal screen as a functional element. In this known air heating box, for which the electrical installation is relatively expensive, the air within the box has the desired temperature only at a certain distance from the base of the box. The temperature gradually increases toward the upper zones or areas of the heating box and may then fall off again over part of the box height, especially toward the outer cover or top lid. Under these circumstances, the same heat treatment of an individual thread or yarn from its entry into the box until its emergence therefrom is not fully assured, and for this reason, one cannot expect the same heat treatment to be applied as between different threads. A completely uniform heat treatment of the many threads being processed by a textile machine is therefore quite difficult to achieve, particularly in large industrial machines. One object of the present invention is to provide an air heating box for use in combination with textile machinery for the continuous transport and heat treatment of threads, whereby uniform quality can be imparted to a large number of threads as well as a consistent and equal quality in each individual thread. Another object of the invention is to construct such an air heating box so as to provide an equal air temperature over the length and width of the box and also a more nearly uniform air temperature over thE height of the box. Yet another object of the invention is to provide an air heating box wherein individual transported threads can be readily loaded at any time without disturbing other thread treatment positions in the same box and with only a very minimal disturbance of the uniform temperature pattern within the box. Another object is to provide an economically constructed and maintained air heating box with easily installed base heating elements along or in combination with other heating means including plate heaters or similar contact heating members. These and further objects and advantages are explained in greater detail hereinafter. It has now been found, in accordance with the invention, that such objects can be achieved in combination with textile machinery for transporting many threads through an air heating box by providing a preferably horizontally elongated box which is substantially enclosed to receive the transported individual threads at spaced intervals over its length, said air heating box further including heating means located in a lower base area or zone of the box, thread entry and exit openings in the form of slots in one wall of the box, preferably one of the bottom and top walls thereof, and thread loading and deflecting rod means adjustably insertable through wall openings adjacent the thread entry and exit slots. The air heating box, with openings in the bottom and usually with a gas or vapor outlet in the top thereof, preferably is constructed with its longitudinal side walls extending in a vertically upward converging or tapering relationship so as to promote a horizontal mixing or diffusion of heated air as well as a normal vertically urged flow of air by heat convection. The thread loading and deflecting means at each thread position essentially includes a supporting rod member slidable in a slotted guide tube and a thread guide member or deflecting element such as a pin, roller or the like connected near the inner end of the supporting rod and extending outwardly therefrom into the adjacent path of the transported thread, i.e. as the thread is guided back and forth within said box from the entry slot around the guide or deflecting means and then back out of the box through the exit slot.

[451 Oct. 31, 1972 United States Patent Treptow et a].

References Cited UNITED STATES PATENTS [54] AIR HEATING BOX FOR TEXTILEMACHINES [72] Inventors: Heinz Treptow,

Ennepetal-Milspe; Benno Frank, Wuppertal-Elberfeld; Heinz Schippers,Remscheid, all of Germany [73] Assignee: Barmag Barmer MaschinenfabrikAktiengesellschaft, Wuppertal, many Ger- ABSTRACT An insulated airheating box for treating threads transported by textile machinerywherein one wall of the 22 Filed: Jul 13, 1971 [21] Appl'No: 162082 boxis provided with entry and exit slots for each thread together with anadjustable thread loading and guiding means insertabie through the samewall [30] Foreign Application Priority Data July 13, 1970 Jan. 22, 1971between or ad'acent to the thread entry and exit slots. German/"WWI, 2034 610's The box is also equipped with one or more different 21 02 956-1heating devices, permitting contact-free heating of the threads and/ordirect heating on a contact plate arranged within the box.

[52] U.S. D, 28/59.5, 28/61 [5 1] Int. l/00, D06c 7/00 [58] Field ofSearch......28/59.5, 61, 62; 68/5 C, 5 D, 23 Claims, 5 Drawing Figures68/5 E; 57/34 HS -PATENTED our 3 1 I972 SHEET 2 OF 3 ATT'YS 'P'A'TENTED0m 3 1 I972 SHEEI 3 0F 3 FIG.5

INVENTORS: HEINZ TREPTOW BENNO FRANK HEINZ SCHIPPERS ATT YS 1 AIRIEATING BOX FOR TEXTILE MACHINES This invention generally relates to anair heating box for the heat treatment of a plurality of yarns orthreads which usually move in approximately vertical direction as theyare transported by conventional textile machines, especially intexturizing, stretching, stretchspooling, stretch-twisting orstretch-texturizing machines. Thus, it is often essential in workingwith synthetic, thermoplastic polymer filaments, threads or yarns toachieve a continuous heat treatment thereof, e.g. for stretching,twisting or texturizing purposes, the same treatment beingsimultaneously applied to a large number of threads as they are rapidlytransported in the textile machine.

For the achievement of uniform quality in each individual thread andalso equal quality of all of the threads among one another,'it isgenerally desirable that the threads be exposed to the same temperatureat all points during their passage in or through the air heating box.

One known air heating box has in its interior a large number ofU-shaped, electrically heated tubes or rods arranged perpendicularly andtransversely to the longitudinal direction of the heating box,additional heating tubes or rods being provided in the region of theheating box base. Between each pair of the threads 1 running from top tobottom once through the rectangular or block-shaped heating box and theheating tubes or rods allocated to these threads, there is arranged asubstantially U-shaped sheet metal screen as a functional element.

In this known air heating box, for which the electrical installation isrelatively expensive, the air within the box has the desired temperatureonly at a certain distance from the base of the box. The temperaturegradually increases toward the upper zones or areas of the heating boxand may then fall off again over part of the box height, especiallytoward the outer cover or top lid. Under these circumstances, the sameheat treatment of an individual thread or yarn from its entry into thebox until its emergence therefrom is not fully assured, and for thisreason, one cannot expect the same heat treatment to be applied asbetween different threads. A completely uniform heat treatment of themany threads being processed by a textile machine is therefore quitedifficult to achieve, particularly in large industrial machines.

One object of the present invention is to provide an air heating box foruse in combination with textile machinery for the continuous transportand heat treatment of threads, whereby uniform quality can be impartedto a large number of threads as well as a consistent and equal qualityin each individual thread. Another object of the invention is toconstruct such an air heating box so as to provide an equal airtemperature over the length and width of the box and also a more nearlyuniform air temperature over the height of the box. Yet another objectof the invention is to provide an air heating box wherein individualtransported threads can be readily loaded at any time without disturbingother thread treatment positions in the same box and with only a veryminimal disturbance of the uniform temperature pattern within the box.Another object is to provide an economically constructed and maintainedair heating box with easily installed base heating elements along or incombination with other heating means including plate heaters or similarcontact heating members. These and further objects and advantages areexplained in greater detail hereinafter.

It has now been found, in accordance with the invention, that suchobjects can be achieved in combination with textile machinery fortransporting many threads through an air heating box by providing apreferably horizontally elongated box which is substantially enclosed toreceive the transported individual threads at spaced intervals over itslength, said air heating box further including heating means located ina lower base area or zone of the box, thread entry and exit openings inthe form of slotsin one wall of the box, preferably one of the bottomand top walls thereof, and thread loading and deflecting rod meansadjustably insertable through wall openings adjacent the thread entryand exit slots.

The air heating box, with openings in the bottom and usually with a gasor vapor outlet in the top thereof, preferably is constructed with itslongitudinal side walls extending in a vertically upward converging ortapering relationship so as to promote a horizontal mixing or diffusionof heated air as well as a normal vertically urged flow of air by heatconvection. The thread loading and deflecting means at each threadposition essentially includes a supporting rod member-slidable in aslotted guide tube and a thread guide member or deflecting element suchas a pin, roller or the like connected near the inner end of thesupporting rod and extending outwardly therefrom into the adjacent pathof the transported thread, i.e. as the thread is guided back and forthwithin said box from the entry slot around the guide or deflecting meansand then back out of the box through the exit slot.

These embodiments and combinations of the invention as well as otherpreferred variations thereof are more fully illustrated and explained inconjunction with the accompanying drawings wherein:

FIG. 1 is a vertical sectional view of a preferred embodiment of ahorizontally elongated air heating box constructed in accordance withthe invention, certain elements being shown in elevation or in partlysectional or schematic form;

FIG. 2 is a section taken along the line 2-2 of FIG. 1 to generallyillustrate the bottom zone of the heating box, a large central portionthereof being omitted;

FIG. 3 is a plan view of a plate or sheet metal base member adapted tobe fastened along the bottom of the heating box to provide thread slotsand other reception openings for two thread positions along one side ofthe box in its longitudinal direction;

FIG. 4 is a fragmented perspective view of a preferred adjustable rodmeans for loading and guiding and individual thread in the air heatingbox; and

FIG. 5 is a partial vertical sectional view of another preferredembodiment of a horizontally elongated heating box provided with heatedcontact plates as additional heating means for the treatment of threadstransported in and out of the box by conventional textile machinery.

Referring first to the embodiment of FIG. 1, the overall heating box 1as a substantially enclosed and insulated casing or housing extendinghorizontally over a large number of textile machine positions isconstructed in a conventional manner of an inner wall or casing 2 and anouter wall or casing 3 with a heat-insulating material 4 enclosedtherebetween. These inner and outer walls 2 and 3 are preferably made ofsheet metal, e.g. a lightweight metal sheeting such as aluminum or thelike. These sheet metal walls canalso be offset or crimped as well asbeing provided with structural supports and/or connecting members togive it sufficient rigidity and strength. I

The entire box can be supported on any suitable framework as indicated,usually by a central elongated framework la along the top of a textilemachine with thread transporting means such as feed rolls or the likecarried 'on either side of this central framework in positions locatedmore or less vertically below the corresponding heat treating positionsin the box 1. In some instances, the thread can be supplied from atextile machine located above the heating box so that the embodimentshown must be slightly modified to supply each thread position of thebox from above rather than from below. Such modifications will bereadily appreciated in terms of only minor changes in the arrangementand construction of individual elements.

Heating elements 5, preferably in the form of two or more tubes or rods6 and 7 as electrical resistance heating means, are essentially arrangedin accordance with the invention along the bottom or base area of theheating box 1. As more fully shown together with FIG. 2, the heatingdevice in its simplest form can consist of two continuous heatingelements 6 and 7 extending over the entire length of the box and acrossthe width of each heating section in the form of a loop near theperiphery of each longitudinal heating section. The ends of these loopscan be connected at a centrally mounted junction box 8 located within oroutside of the heating box and supplied with electrical current in aconventional manner from an external source.

The individual threads 9 being supplied from the textile machineryassociated with the lower supporting framework la enter into the bottomof the heating box 1 through suitable thread slots and other openingswhich are described more fully below but which may also serve as inletmeans for fresh air. Of course, other openings in the bottom of the box1 can also be provided for the intake of air, particularly if the threadentry and exit slots and supporting members enter from the top of thebox 1. The base installed heating device is essentially devoted to theheating of fresh air entering the bottom zone of the box 1, for examplefrom an ambient room temperature of about 30C. up to the desired airtemperature within the heating box of approximately 230C. as but oneexample. This heating device 5 can also serve to maintain the desiredtemperature within the box 1 by replacing heat absorbed by the threadsor heat lost through expelled gases or vapors and/or by heat conductiongradually through the insulated walls. In this respect, theheat-insulation material 4 contributes substantially to the efiiciencyof the device in terms of such heat loss, but the relatively low heightof the heating box 1 is also a very significant factor.

The threads 9 enter at the bottom of the box 1 as indicated by theupwardly directed arrow, are deflected near the top of the box and arethen withdrawn outwardly in the direction of the downwardly directedarrow on the opposite side of the rod means 10.

Suitably thread entry and exit slots as well as openings for the rodmeans 10 are thus provided entirely on the entry side of the heating box1, this being the bottom or base side of the box in the illustratedembodiment. It is equally possible, however, to have the threads enterand leave the top or upper side of the heating box without losing any ofthe advantages of the invention. In this case, the box can still haveits preferred shape in the sense of upwardly converging longitudinalsides, e.g. so as to provide a vertical transverse cross-section of thebox interior which has a substantially trapezoidal shape. a

This preferred trapezoidal shape or modifications thereof which permit agradual reduction of successive interior horizontal cross-sections asone proceeds upwardly in a vertical direction is believed to be at leastpartly responsible for the surprisingly good results achieved with theair heating box of the invention;

other factors may also be considered as contributing to such successfulresults which are achieved at relatively low cost in terms ofconstruction and electrical installation and maintenance.

The arrangement of the heating device 5 in the bottom zone of theheating box 1 leads to the result that the air entering at the bottom ofthe box immediately reaches its desired temperature and, by reason ofconvection over the relatively short distance from bottom to top of thebox, tends to bring theentire region lying above the base to this sametemperature, without it being necessary to install additional heatingelements above the base.

Through the installation of the entire heating device essentially in thebottom region of the heating box, there also takes place over thisbottom area a more or less even heating of the entire inner wall orcasing 2 consisting preferably of aluminum sheeting. Since the innerwall 2 is surrounded with a thick heat insulating layer 4 and themetalouter casing 3, the heat loss or rate flow-off to the outside is keptquite low.

The feature of running the thread into the heating box on one side, thendeflecting the thread within the heating box and running it out againfrom the entry side should also participate in the overall desiredresult, Le. a practically equal temperature over the entire interior ofthe box. Thus, with heating means disposed in the bottom zone, the airtemperature over the height of the heating box is maintained constantmore easily as the height of the heating box is reduced. In this sense,the transport of the thread in and out of the heating box on the sameside, e.g. the bottom or top of the box, has an advantageous efi'ect.With equal thread running length within the heating box as in knownboxes, the height of the box can be considerably reduced even with onlyone traverse of the tread between the top and bottom of the box.Thereby, the structural height of the entire textile machine in whichthe air heating box is installed can also be reduced in a mostadvantageous manner.

It is also most desirable for the maintenance of a substantiallyconstant air temperature in the heating box to simplify the threading orthread-loading procedure so that the introduction of a transportedthread can be carried out in the shortest possible time. This thirdmeasure which is essential to the invention, namely fastening a threadguide or deflection means to an adjustable rod whereby the thread can beintroduced into the heating box andthen held therein in a specific path,permits the thread to be quickly loaded or applied in its properheat-treating position without the temperature equilibrium beingappreciably distrubed. This thread loading or inserting means equippedwith a guide or deflecting element on an adjustable rod is describedmore fully below.

A preferred embodiment-of the air heating box according to the inventionis also characterized by an interior horizontal cross-section whichessentially diminishes upwardly in vertical direction. Through such across-sectional tapering of the heating box from the bottom upward andthe oblique or converging walls provided by this construction, thereresults a further temperature equalization. In particular, theconverging longitudinal side walls contribute to the extent that theheated and rising air receives an appreciable horizontal flow component,so that there takes place a temperature balancing effect between the twohalves of the heating box across the longitudinal central or bisectingvertical plane.

For reasons of construction and manufacturing, the cross-sectionaltapering is best carried out in such a way that the verticalcross-section has a trapezoidal shape perpendicularly to thelongitudinal mid-plane or bisecting vertical plane along thelongitudinal and horizontal axis of the box. The trapezoid is preferablyan isoceles trapezoid, i.e. as represented by the longitudinal sidewalls providing spaced treating positions in each half of the heatingbox separated by the midplane.

In order to achieve a temperature balancing in the longitudinal andhorizontal direction of the heating box, i.e. over the entire sequenceof spaced thread transporting or treatment positions, a furtherpreferred embodiment of the air heating box is characterized by theheating device consisting of a plurality of heating elements extendingover the entire length of the heating box. If one of these heatingelements should drop out or fail to function, then the heat output ofthe intact heating elements can be adjusted individual heating elementsillustrated, they means of a central temperature sensor or thermostat insuch a manner that the desired temperature is maintained. In addition tothe single set of individual heating elements illuatrated, they can alsorun horizontally next to one another or over one another in the bottomportion of the box. Frequently it is expedient to unit the heatingelements into a single element encompassing the entire heating boxlength and width, i.e. as with the looped elements illustrated. ln allcases, these base heating elements are maintained free of contact withthe running threads.

The above-mentioned measures all provide a better temperature balancingin vertical and/or horizontal direction and are therefore ideallycombined for optimum effect. As stressed, at the outset, however, inloading or applying the thread into the heating box, care must be takenthat the temperature equilibrium within the box is not overly disturbed.

In order to accomplish a threading or loading of a stationary or runninglength of thread or yarn into the heating box both surely and rapidly,the invention includes an especially preferred embodiment of the loadingand deflecting means 10 in the form of adjustable rods 12 which can beinserted into or extracted from the heating box 1 while being guided orheld slidably in a relatively close-fitting guide tube 11 whichpreferably has a square cross-section as shown most clearly in FIG. 4.

This guide tube 11 is preferably detachably fastened at its upper orinner end by inserting it into a sleeve or socket member 13 fixed on theupper cover or top side of the box, e.g. using any suitable means toanchor the guide tube in this socket so that it can subsequently bedetached and withdrawn if necessary for periodic cleaning ormaintenance. At the bottom or on the exterior of the entry side of thebox 1, the guide tube 1 l is preferably held firmly in place by a collaror releasable locking clip 14, the tube 11 then extending or projectingdownwardly from the box 1 for a distance of preferably in the range ofabout one-third of its total length.

If the threads enter and exit through the top of the heating box, it isobviously feasible to introduce the rods 12 downwardly in guide tubes 11from above the box and to withdraw these rods upwardly. However, sincethe heating box still preferably retains its trapezoidal shape withlongitudinal side walls tapering or converging in an upward direction,it is expedient to displace the adjustable rod means 10 alternately oneach side of the box at offset longitudinal positions, i.e. alternatelyparallel first to one side wall and then the other side wall. Thisavoids any interference when withdrawing rods simultaneously from bothsides of the box in adjacent positions or approximately opposingpositions. Also, minor variations are obviously required as to theplacement or arrangement of other elements to avoid any possibleinterference with the function of the loading and deflecting rod means.

Each guide tube 11 which fits into the square opening 15(FlGS. 2 and 3)has a longitudinal slot lla along one edge thereof as shown in detail inFIG. 4. Through this slot which appears over substantially the entirelength of the guide tube 11, there extends a supporting bracket orcantilever arm member connected rigidly to the upper or inner end of therod 12 so as to carry at an extended position a suitable thread guide ordeflecting member such as the small roller or pin 16b (this deflectingor guide means being indicated at 16 in FIG. 1 wherein the slot 11a isnot illustrated). The thread 9 travels upwardly to this guide ordeflecting pin 16 in the rising path 17 and then returns therefrom inthe descending path 18.

The threading or loading of each thread treatment position along thelength of the heating box and on either side thereof takes placeessentially as follows. First, the rod 12 is drawn out by its handle 19after first releasing the safety catch 20 which fits into an opening orrecessed arresting hole 20a in the side of the guide tube 11. Thissafety catch is spring urged on a pivot within handle 12 as indicated sothat it automatically locks this rod when shifted or shoved into itsfully inserted position in the slotted guide tube 11. When the rod 12 iscompletely withdrawn, the guide or deflecting element 16 protruding orconnected through slot 1 la is also lowered beneath the bottom of thebox through suitable openings so that it is readily accessible forthread loading. Thus, the thread is simply placed on or looped over theupper surface of the pin or roller 16a and this deflecting means is thenshoved upwardly with the adjustable rod 12 until the safety catch orlatch means 2% again locks this rod in its normal operating positionwith theguide element 16 near the top of the heating box as indicated inFIG. 1. Y

The bracket or arm 16a carrying the guide pin or roll 16!; isadvantageously fastened at the inner or free end of adjusting rod 12 soas to run approximately parallel to the longitudinal axis of the heatingbox 1 as can be generally perceived from the arrangement of partsincluding their corresponding openings or slots in the bottom of theheating box, all as shown in FIGS. 1-3. Thus, while the rods 12 areinserted at a'slight angle to the vertical, the thread guide element 16is moved up and down with the guided thread remaining in a substantiallyvertical plane transverse to the longitudinal axis of the heating box.

The slight inclination of the guide tubes 11 for slidably inserting andwithdrawing the rods 12 has the further advantage that the rods can befully withdrawn without running-into or interfering with thread run-offspools or winding bobbins or the like (not shown) which are usuallymounted directly below the heating box 1 on the textile machine frame 1aas further indicated by the inwardly directed path 18 of the downwardlydirected threads leaving the heating box. The same advantage applieswhere the threads enter and exit at the top of the heating box withreference to feed and/or winding spools on an upper machine frame.

In both instances, the rods 12 preferably travel parallel to thelongitudinal shanks or sides of the trapezoidal box.

The most ideal construction of the heating box 1 to accommodate thispreferred inclined adjustment of the thread guide and loading rods 12 isone in which the wall or side of the box containing the thread entry andexit slots consists essentially of two halves or separate longitudinalbottom wall members abutting on a longitudinal central plane or verticalmidsection of the box and extending obliquely therefrom out to join at aright angle with the longitudinal side walls extending parallel to thelongitudinal axis of the box. The guide tubes 11 with adjustable rods 12can then be easily arranged perpendicularly to each half of the bottomwall in positions adjacent their respective thread entry and exit'slots.

Still another advantageous feature of the invention is to provide aheat-insulating or protection tube 21 as shown in FIGS. 1 and 4 whichrests freely slidable on the bottom end of the guide tube 11 and ispreferably perforated to increase its cooling or protective effect. Whenthe rod 12 is in its fully inserted and normal operating position, thisadditional protective tube 21 is seated on a stop 12a which travels ashort distance into the exposed slot 11a of guide tube 11. Then, whenthe rod 12 is drawn downwardly, the heat protection tube 21 likewiseslides freely downward until its inwardly protruding upper flange or lip22 comes to rest on the stop members 23 at the lower end of the guidetube 11. (See FIG. 1 for these stop members 23 which are enclosed at thelower end of perforated tube 21 in the closed position of the rod means9 in FIG. 4.)

This telescopic arrangement of the outer heat-protection tube 21encloses the outer extension of the interfitting slotted guide tube 11and the adjusting rod 12 when both the guide tube and its rod are in thefully inserted position, i.e. over approximately one-third'the length ofthe rod and guide tube assembly. When releasing the safety catch 20 andwithdrawing the rod 12, the heat-protection tube 21 slides outwardlyover the guide tube 11 so as to always enclose at least that portion ofthe withdrawn rod 12 projecting immediately adjacent the external fixedend of the guide tube 11. In the fully withdrawn position, one canreadily visualize the fact that the tube and rod telescopic assemblyextends axially on the outside of the heating box 1 such that the firstthird of its length is represented by the exposed guide tube 11 down tostop 23, the second third of its length corresponds to the middle thirdof rod 12 surrounded by the heat-protection tube 21 while the last thirdof its length is the exposed end portion of the rod 12. In this mannerthe outer perforated tube 21 effectively shields precisely that portionof rod 12 which is normally contained in the lower part of box 1 and istherefore at an elevated temperature and quite hot after first beingwithdrawn. in order to enclose all of the upper two-thirds of thewithdrawn rod 12, i.e. in-

"cluding its upper one-third which remains within guide tube 11, it isalso feasible to divide the protective tube 21 into an upper section 21aretained by stop means 23a and telescopically fitted into the freelyslidable lower section 21b, as further indicated in FIG. 4. Nor- 4mally, however, guide tube 11 provides sufficient heat protection forthe withdrawn heated rod 12 immediately adjacent the box 1.

As noted above, the air heating box of FIG. 1 as well as that of theembodiment shown in FIG. 5, has the profile of an isosceles trapezoid ina vertical section transverse to the horizontal longitudinal axis of thebox, the smaller base side being on top and the larger base side of thetrapezoid representing the bottom of the box. However, rather thanproviding a horizontal base side, it is especially advantageous toprovide a bottom consisting of detachable wall plates or longitudinalsegments 24 which can be fastened to extend approximately perpendicularto the respective longitudinal side walls 25 on either side of thelongitudinal midsection of the box.

Suitable. inlet pipes or conduits 26 can further be provided, e.g. inside walls 25, for the introduction of steam into the air heating box 1.This improves the heat transition to the threads, especially where astrongheat-tixing effect is desired as in the treatment oftorque-crimped threads or yarns.

The trough or gutter formed by the obliquely positioned bottom walls 24of the box 1 can be provided with one or more discharge outlets 27 forthe collection and withdrawal of a liquid condensate, for example steamcondensate and/or the condensate formed by finishing agents or the like.The discharge pipe or pipes 27 can be directed away from the textilemachine by any suitable connecting line or collecting vessel (notshown).

Most of the vapors or gases arising from finishing agents or the likeemerge at the top or cover of box 1 and can be drawn off through anumber of outlet apertures 27, for example into a corresponding numberof apertures or openings in a suction tube 270 which extendslongitudinally over the top of the box 1, preferably on an independentsupport means 27b without being directly connected to the box so as toprovide a slight air gap 28 between the separately supported tube andthe cover of the box.

As shown in greater detail in FIGS. 2 and 3, the thread loading anddeflecting adjustable rod assemblies 10 are arranged in rows along eachof the upwardly converging side walls 25 along the inner wall surface ata distance sufficient to clear the looped heating elements 6 and 7. Theindividual slidable rods 12 in guide tubes 11 are introduced into thebox through the square openings 15 spaced at regular intervals in rowsparallel with the longitudinal axis of the box. The square cross-sectionof openings 15 and guide tubes 11 is selected so that the guide tubewill not turn or twist about its longitudinal axis. Any cross-sectionother than a circular one is generally suitable or else other means mustbe provided to prevent the undesired twisting.

The enlarged view of FIG. 3 illustrates in detail one plate or segment24 on one longitudinal side of the heating box 1 and shows the manner inwhich the threading and guiding elements are received through the bottomof the box 1 in relation to suitably positioned thread entry and exitslots. In particular, an elongated opening or slot 29 extendslongitudinally from one of the square tube-receiving openings 15 in adirection substantially parallel to the longitudinal axis of the box,this longitudinal slot being adapted to permit the passage of thebracket or arm 16a of the thread guide means through the bottom of thebox. At the same time, the approximately square shaped opening 30 isadapted to receive the thread guide or deflecting element 16b at arelatively short longitudinal interval from the opening 15. In thisinstance, the square opening 30 is turned so that one diagonal isparallel to the longitudinal direction of the heating box 1 and falls onthe longitudinal centerline of slot opening 29. The other diagonal ofthe square opening 30 leads into a transverse elongated slot whichextends from the two transversely disposed corners of opening 30 toprovide a thread entry slot 31 and a thread exit slot 32 for thereception of the thread courses or paths 17 and 18,.

respectively.

These thread entry and exit slots, which are arranged on a commoncenterline perpendicular to the centerline of slot 29 corresponding tothe axis of guide member 16b, should be relatively narrow so as toprovide suitable thread guides. For this reason, also, the slots arepreferably lined along at least the outer ends thereof with anabrasion-resistant and wear-proof material 33, e.g. very hard surfacedmetal coatings or ceramic linings or the like. Since such surfaces arealso quite smooth, they prevent inadvertent or undesirable threaddamage, e.g. even when the thread is traveling as it is loaded or guidedthrough these entry and exit slots into or within the air heating box.

The elongated opening 29 can continue on as a connecting slot 3 3 fromthe opposite corner of square opening 3d up to the next adjacenttube-receiving opening 15 which is then associated with another set ofopenings (29', 30') identical to those first described, including thenext set of adjacent transverse thread entry and exit slots (31', 32).In some instances, it is preferable to mount two of the thread guide ordeflection elements 161) and 16b in sequence on a single bracket orcantilever arm (16a, 16a) extending from the first described rod 12longitudinally in slot 29 to reach both openings 31) and 30, for exampleby merely extending the bracket or arm 16a as indicated by the dottedlines 35 to include segment 16a as part of a single supporting arm, i.e.while omitting the second tube and rod assembly (11, 12).

This means that two thread positions can be loaded simultaneously, i.e.by simply extending the arm 16a beyond guide pin 16b as shown in FIG. 4to support another guide pin on the same longitudinal axis. Of course,it is also feasible to mount one or more additional brackets and guidemeans 16 at vertically spaced intervals on rod 12, preferably whileoffsetting the thread courses slightly and providing separate entry andexit slots for the different thread courses. These and similarvariations represent substantially equivalent structures for purposes ofthe present invention.

The individual plate or sheet metal segment 24 shown in FIG. 3preferably contains only two up to about four longitudinally spacedthread loading and guiding positions on each side of the midsection ofthe heating box. Such plates 24 can be in the form of individual panelswhich are preferably adapted to be inserted in recesses in the outerwall 3 of the bottom of the box 1 and attached to this outer wall orsupporting struts thereon or the like by means of bolts or otherfastening means through the-bores 36 and 37. Similar openings in thebottom inner wall 2 can be directly provided so as to correspond inapproximate shape and location to those of the outer wall 3. The threadreceiving slots 31,32 and 31',32, etc. are preferably made larger in theinner wall 2 so that only those slots in the outer wall 3 serve asthread guides.

Of course, one can also provide these bottom panels 24 in the form ofdouble-walled units with preloaded insulation such that an individualpanel extends substantially over its half of the bottom of box 1 or onlyover an outer portion thereof as indicated by the dotted longitudinallines 38 in FIG. 2. Thus, such panels or walls can also be hinged orotherwise removably held along inner edge 38 by means of a hinge orholding member 39 along supporting brace 40 of the machine frame 1a(FIG. 1). This permits very easy access to the interior of the box forcleaning purposes or for maintenance, e.g. in replacing heating rods orguide tubes.

The air heating box 41 of FIG. 5 is generally similar to that shown inFIG. 1 in the sense that it is elongated in a horizontal direction andhas an inner sheet metal wall 42 and outer wall 43 with suitableinsulating material 44 therebetween. However, in addition to a baseheating device 45, which is essentially located only in the bottom zoneof the heating box and which can again be made up of a number ofelectrically resistance-heated rods or looped heating elements, suppliedwith current feed through electrical lines 46, this embodiment of FIG. 5further includes contact heating plate means 47 and 48 arranged to beplaced in direct running contact with the transported thread 49 as itgoes upwardly and/or downwardly again out of the box. The heating box 41also preferably has an approximately trapezoidal shape with upwardlyconverging longitudinal side walls so as to achieve the desired heatingeffect from this shape.

The thread loading and deflecting means 50 can be constructed as in theprevious embodiment for vertical thread loading but is shown more simplyin the present instance as the adjusting rod 51 with a deflecting roller52 at its upper end and slidably adjusted in the bracket holder 53 bymeans of rod handle 54. Thus, to install the thread 49, the rod 51 ispulled out until roller 52 is beneath the bottom outer wall 42 for easyapplication of the thread to roller 52 and reinsertion of the rod 51.

In the illustrated embodiment of FIG. 5, each individual thread 49 isprovided on its entry side as well as on its exit side with the contactplates 47 and 48 which have convex contacting surfaces 55 and 56,respectively, an are composed of a good heat-conducting material such asany conventional heatable metallic materials preferably with arelatively abrasion-resistant outer convex contacting surface. It isusually desirable to provide for each thread or for a single thread paironly one contact plate 47 or 48, i.e. so that these contact plates havea width of the thread contacting surface in the longitudinal directionof the box which is quite narrow and sufiicient only to accommodateminor fluctuations in the running course or path of the individuallyheated thread.

Both heating plates 47 and 48, as illustrated, have approximately thesame construction, but contact plate 47 is free of any other devices soas to be heated solely by the air or gases in the box while contactplate 48 contains a thermocouple 57 and an electrical resistance heatingelement 58. This permits an additional carefully controlled heating ofthe thread 49 just before it exits from the heating box, e.g. so thatthe thread'is very quickly adjusted to a final fixing temperature.

such internally heated plates, i.e. so as to carefully'adjust thetemperature indicated by thermocouple 57 over current supply wires 59 tothe internal electrical resistance heating element 58. Such temperaturecontrol means are not otherwise illustrated since they are usuallymounted externally of the machine for adjusting the temperature of alarge number of thread treating units.

A ventilation or exhaust opening 66 can be provided in the upper coveror top of the heating box, preferably directly above the guide element52, to withdraw the vapors of finishing agents and to gradually withdrawair therewith. The thread entry and exit slots 69 as well as theopenings for adjusting rod assembly can be partly or almost completelyblocked off during operation to adjust air flow into the bottom of thebox. One can also provide other air openings with any suitable: meansfor regulating the size of such openings with respect to the air intake.

Also, access to the interior of the box 41 can be advantageouslyprovided by removable side panels or doors 67 extending over at least aportion of the length of the box. Such panels or doors are removablyfastened by the bolts 68 but otherwise provide the double-walled andinsulated construction of the remainder of the box. Access for cleaningpurposes is generally necessary from time to time because, on the onehand, thread particles such as fluff, lint or dust collects in theheating box and, on the other hand, vapors of textile finishing agentswhich are usually oily preparation tend to precipitate or condense onthe contact plates to form a solid brownish rust thereon which must beperiodically removed. Furthermore, worn contact plates or differentlydesigned plates can be changed.

In order to effectively mount and position the heated contact plates 47and 48, it is desirable to provide parti- I tions 60 and 61 which extendover the length of the Conventional means for balancing the temperatureof heating box 41 and which also consist of a metal or other material ofgood heat conducting properties so that they can function as additionalheat-distributing or temperature-balancing members. In order to permitor allow a certain amount of heat expansion play, thesecarrierpartitions 60 and 61 are preferably mounted at only one fixed orstationary point, for example at the top ends thereof by the mountingbrackets 62 and 63, respectively, using any suitable bolt or screwfastening means. Such a fixed point is preferably in the middle of thenarrow partition 60 or 61. This fastening at the upper end only and inthe manner shown permits the carrier partitions to expand horizontallyin both longitudinal and transverse directions. The outermost partition60 is of course arranged at a spaced interval from the facing inner sidewall 42 of the box, and partition 61 is further spaced inwardly at anappropriate distance.

At their lower edges, the carrier partitions 60 and 61 are merely guidedor loosely held in the slotted or grooved holders 64 and 65,respectively, which in turn are connected rigidly in any suitable mannerto the bottom of the heating box 41. In this manner, the carriers 60 and61 are given substantial freedom at their bottom end for heat expansionplay. Such means for allowing play to accommodate the effects of heatexpansion serve to avoid excessive strain or dislocation of thesecarriers and the contact heating plates 47 and 48 which are attachedthereto and supported thereby with con ventional fastening means such asbolts, screws, pegs,

tongue and groove connections or any similar means. It

is desirable to provide an intimate or flush contact of theheat-conducting and joined surfaces of plates 47 and 48 with theirrespective carriers 60 and 61.

An identical arrangement of such contact heating plates and carrierpartitions with the associated thread loading and guiding elements iscontained in the other half of box 41 as only partly indicated in FIG.5.

These additional contact heating plates for direct heating of thetransported threads are of substantial advantage when combined with thebase heating elements of the invention in that one can achieve a muchmore rapid heating of the thread while still maintaining a substantially equal temperature over the entire interior of the air heatingbox.

It is quite often preferable to heat the entering thread exclusively bythe heated air, i.e. free of any contact by omitting plate 47 and itscarrier 60, since at this point the temperature difference between theair and the thread as it enters is still relatively great so that theheat transfer to the thread by heat convection in air is correspondinglylarge and effective. Then, by passing the exiting thread over thecontact plate 48, it is quickly brought to its final temperature withcomplete certainty. Such a combination is then ideally suited to hightemperature fixing of threads, yarns and similar filamentary materialscomposed of thermoplastic, synthetic fibrous polymers, especially incrimped or texturized form.

Although the effective contact surface between the running thread andone or both heated convex plates can remain relatively small, theeffective contact sur face of these plates with the surrounding air isvery great, especially with the cooperation of the additional surfaceareas presented by the carrier partitions. This assures that the platesremain at approximately the mean or average air temperature in the box,this air temperature in turn being balanced or equalized by the heatingplates. The thread is then brought to this same temperature beforeleaving the air heating box.

With the combined heating devices of FIG. 5, the overall height of theair heating box can be path reduced and a single traversing apth of thethread over the relatively short distance between the top and bottom ofthe box is sufficient under normal operating conditions to provide anefiective heat treatment of a wide variety of textile threads,filaments, yarns and the like. At the same time, all of the advantagesof rapid threading or loading of individual thread treatment positionsare achieved without disturbing the uniform and highly equalized orbalanced temperature maintained in the air heating box.

The various heating devices and combinations of apparatus shown hereinare merely illustrative of the invention and its essential features andcharacteristics. It is of course a further advantage of the inventionthat individual elements are relatively easily obtained or fabricatedand that the air heating box itself is readily adapted to be used withexisting textile machines of all types.

The invention is hereby claimed as follows:

1. In an air heating box for the heat treatment of a plurality ofthreads being transported by textile machinery in combination therewith,the improvement which comprises:

an elongated and substantially enclosed heating box to receivetransported individual threads at spaced intervals over its length;

heating means located in a lower base area of said box;

thread entry and exit slots in one wall'of said box;

and

thread loading and deflecting rod means adjustably insertable throughwall openings adjacent said thread entry and exit slots.

2. An air heating box as claimed in claim 1 wherein the bottom wall ofsaid box is provided with said thread entry and exit slots.

3. An air heating box as claimed in claim 1 wherein the top wall of saidbox is provided with said thread entry and exit slots. 7

4. An air heating box as claimed in claim 1 elongated in the horizontaldirection and having an interior horizontal cross-section which reducesin an upward vertical direction.

5. An air heating box as claimed in claim 4 wherein a verticaltransverse cross-section of the box interior has a substantiallytrapezoidal shape.-

6. An air heating box as claimed in claim 4 wherein said heating meansincludes a plurality of heating elements extending horizontally over theentire length of the box interior adjacent its bottom wall.

7. An air heating box as claimed in claim 6 wherein several longitudinalheating elements are joined to encompass the entire width and length ofthe box interior adjacent its bottom wall.

8. An air heating box as claimed in claim 1 wherein said adjustable rodmeans include for each individual thread a slotted tubular guide meansfastened to said box and extending between the top and bottom thereof toslidably receive a supporting rod having a thread guide means extendingoutwardly therefrom and connected near the inner end of the rod toprovide a deflection surface around which the entering thread isreturned to an exit slot in the entry wall.

9. An air heating box as claimed in claim 8 wherein each said adjustablerod means extends outside of the thread entry and exit wall of the boxto provide a slotted guide tube and supporting rod assembly arrangedtelescopically with an outer heat-protection tube enclosing the outerextension of both said guide tube and rod of said assembly in its fullyinserted position said heat-protection tube being adapted to slideoutwardly over said guide tube together with the withdrawal of said rodto enclose at least a portion of the withdrawn rod projecting adjacentthe external fixed end of said guide tube.

10. An air heating box as claimed in claim 9 including safety catchmeans locking the telescoping supporting rod, guide tube andheat-protection tube in place in the fully inserted position of saidsupporting rod.

11. An air heating box as claimed in claim 1 wherein said wallcontaining said thread entry and exit slots is composed of two halvesabutting on a longitudinal central plane and extending obliquelytherefrom to receive individual threads on either side of said centralplane, each half of said wall forming a right angle with the adjoiningside wall extending parallel to the longitudinal axis of the box, andwherein. said rod means are arranged perpendicularly to each half ofsaid wall adjacent respective thread entry and exit slots.

12. An air heating box as claimed in claim 11 elongated in thehorizontal direction and having side walls tapering upwardly in thevertical direction to provide an interior heated space which isgradually reduced in volume from the bottom toward the top of the box.

13. An air heating box as claimed in claim 8 wherein said rod meansincludes a plurality of thread guide means at the inner end of eachadjustable rod insertable through a wall opening.

14. An air heating box as claimed in claim 8 wherein means are providedto vibrate said thread guide means.

15. An air heating box as claimed in claim 1 wherein said thread entryand exit slots are lined at the ends thereof with an abrasionandwear-resistant material where the slots are contacted by a runningthread.

16. An air heating box as claimed in claim 1 wherein the bottom wall isprovided with sufficient inlet openings to admit fresh air forcirculation through said box and the upper wall of said box containsoutlet openings to withdraw air and any other gases or vapors generatedby the heat treatment of the thread.

17. An air heating box as claimed in claim 16 containing means forintroducing steam into the interior of the box.

18. An air heating box as claimed in claim 17 having means to dischargeliquid condensate from the bottom of the box.

19. An air heating box as claimed in claim 1 wherein the interior of thebox is substantially free of air obstructing elements other than saidheating means and said rod means so that each thread is transported freeof contact back and forth from a thread entry slot to at least onerod-supported deflecting point and then outwardly through a thread exitslot.

16 means permitting heat expansion play.

22. An air heating box as claimed in claim 20 wherein said heatingplates contain an electrical resistance heating element.

23. An air heating box as claimed in claim 20 wherein said heatingplates contain a thermocouple for regulation of the heat supplied tosaid threads.

1. In an air heating box for the heat treatment of a plurality ofthreads being transported by textile machinery in combination therewith,the improvement which comprises: an elongated and substantially enclosedheating box to receive transported individual threads at spacedintervals over its length; heating means located In a lower base area ofsaid box; thread entry and exit slots in one wall of said box; andthread loading and deflecting rod means adjustably insertable throughwall openings adjacent said thread entry and exit slots.
 2. An airheating box as claimed in claim 1 wherein the bottom wall of said box isprovided with said thread entry and exit slots.
 3. An air heating box asclaimed in claim 1 wherein the top wall of said box is provided withsaid thread entry and exit slots.
 4. An air heating box as claimed inclaim 1 elongated in the horizontal direction and having an interiorhorizontal cross-section which reduces in an upward vertical direction.5. An air heating box as claimed in claim 4 wherein a verticaltransverse cross-section of the box interior has a substantiallytrapezoidal shape.
 6. An air heating box as claimed in claim 4 whereinsaid heating means includes a plurality of heating elements extendinghorizontally over the entire length of the box interior adjacent itsbottom wall.
 7. An air heating box as claimed in claim 6 wherein severallongitudinal heating elements are joined to encompass the entire widthand length of the box interior adjacent its bottom wall.
 8. An airheating box as claimed in claim 1 wherein said adjustable rod meansinclude for each individual thread a slotted tubular guide meansfastened to said box and extending between the top and bottom thereof toslidably receive a supporting rod having a thread guide means extendingoutwardly therefrom and connected near the inner end of the rod toprovide a deflection surface around which the entering thread isreturned to an exit slot in the entry wall.
 9. An air heating box asclaimed in claim 8 wherein each said adjustable rod means extendsoutside of the thread entry and exit wall of the box to provide aslotted guide tube and supporting rod assembly arranged telescopicallywith an outer heat-protection tube enclosing the outer extension of bothsaid guide tube and rod of said assembly in its fully inserted positionsaid heat-protection tube being adapted to slide outwardly over saidguide tube together with the withdrawal of said rod to enclose at leasta portion of the withdrawn rod projecting adjacent the external fixedend of said guide tube.
 10. An air heating box as claimed in claim 9including safety catch means locking the telescoping supporting rod,guide tube and heat-protection tube in place in the fully insertedposition of said supporting rod.
 11. An air heating box as claimed inclaim 1 wherein said wall containing said thread entry and exit slots iscomposed of two halves abutting on a longitudinal central plane andextending obliquely therefrom to receive individual threads on eitherside of said central plane, each half of said wall forming a right anglewith the adjoining side wall extending parallel to the longitudinal axisof the box, and wherein said rod means are arranged perpendicularly toeach half of said wall adjacent respective thread entry and exit slots.12. An air heating box as claimed in claim 11 elongated in thehorizontal direction and having side walls tapering upwardly in thevertical direction to provide an interior heated space which isgradually reduced in volume from the bottom toward the top of the box.13. An air heating box as claimed in claim 8 wherein said rod meansincludes a plurality of thread guide means at the inner end of eachadjustable rod insertable through a wall opening.
 14. An air heating boxas claimed in claim 8 wherein means are provided to vibrate said threadguide means.
 15. An air heating box as claimed in claim 1 wherein saidthread entry and exit slots are lined at the ends thereof with anabrasion- and wear-resistant material where the slots are contacted by arunning thread.
 16. An air heating box as claimed in claim 1 wherein thebottom wall is provided with sufficient inlet openings to admit freshair for circulation through said box and the upper wall of said boxcOntains outlet openings to withdraw air and any other gases or vaporsgenerated by the heat treatment of the thread.
 17. An air heating box asclaimed in claim 16 containing means for introducing steam into theinterior of the box.
 18. An air heating box as claimed in claim 17having means to discharge liquid condensate from the bottom of the box.19. An air heating box as claimed in claim 1 wherein the interior of thebox is substantially free of air obstructing elements other than saidheating means and said rod means so that each thread is transported freeof contact back and forth from a thread entry slot to at least onerod-supported deflecting point and then outwardly through a thread exitslot.
 20. An air heating box as claimed in claim 1 including a pluralityof contact heating plates mounted in the interior of said box andarranged with a convex surface for running contact with each thread. 21.An air heating box as claimed in claim 20 wherein said heating platesare mounted on carrier partitions extending over the length of the box,said partitions being fastened to the inner walls of the box with meanspermitting heat expansion play.
 22. An air heating box as claimed inclaim 20 wherein said heating plates contain an electrical resistanceheating element.
 23. An air heating box as claimed in claim 20 whereinsaid heating plates contain a thermocouple for regulation of the heatsupplied to said threads.